In general, motorcycles are equipped with a body—or frame—on which handle bar 10 is mounted, two—a pair of—wheels 30 that are installed onto front and rear side of the body 20, an engine (not illustrated) for generating power that is mounted on the body, drivelines (not illustrated) that transfer the power generated by the engine, a brake system (not illustrated) that control revolution speed of wheels 30. The body is equipped with a saddle on which driver sit.
Driving power is generated by the engine of the motorcycle, and delivered to the wheels 30. The wheels 30 rotate by driving power delivered via the drivelines. The motorcycle drives by rotation of the wheels 30 that keep contact with the ground.
The brake system can be activated in order to stop the motorcycle.
The brake system reduces speed of revolution of the wheels 30 and then stops the wheels 30. By stopping the wheels 30 the motorcycle can be brought to a standstill.
The driver put each of his foot to the ground to support the motorcycle when the motorcycle is stopped. The motorcycle is almost perpendicular to the ground then. When the driver drives the motorcycle driving power generated by the engine is delivered to the wheels again to rotate the wheels.
In the meantime, the driver stands the motorcycle with the help of the supporting unit equipped on the body when he do not wishes to drive the motorcycle that is already in stopped status—when he wishes to park the motorcycle.
According to an example of the supporting unit, a rotatable stanchion is connected to lower part of the body, and the stanchion and the body is linked by a spring. In particular, one end of the stanchion is connected to a pin that is equipped on the body. One end of the spring is connected to the body and the other is connected to the other end of the stanchion.
The stanchion maintains horizontality against the ground when the motorcycle drives by the elastic force of the spring. The driver moves the stanchion to the position that is almost perpendicular to the ground when he stops the motorcycle. Then, he leans the motorcycle to the direction of the stanchion for the stanchion to contact with the ground. The stanchion, front wheel and rear wheel are supported by the ground so that the motorcycle can be a standstill. And the driver moves the stanchion to a position that is horizontal to the ground when he drives the motorcycle.
However, when the motorcycle stops for a moment in driving the driver sitting on the saddle should put each of his foot to the ground in order to support the motorcycle. If both of his feet do not reach for the ground coincidely, the driver should lean the motorcycle to a direction to support the motorcycle by one of his foot that reaches for the ground.
It do not require so much power to support the motorcycle—that is, a small amount of force is loaded to the foot of the driver—when it is perpendicular to the ground, because the center of mass of the motorcycle is perpendicular to contact point with the ground (when seen at the front). However, the driver will potentiate his foot to support the motorcycle—more amount of force will be loaded to the foot of the driver—when the motorcycle begins to tilt.
In particular, the heavier the motorcycle became, the more force loaded to the foot of the driver to support the motorcycle. If the driver can not stand the motorcycle by one foot when it is inclined, the motorcycle will fall down. It is not easy to stand the fallen down motorcycle again if the motorcycle is heavy by oneself.
Furthermore, the motorcycle is not much stable when parked after driving because it merely supported by a stanchion and two wheels.